1. Field of the Invention
The present invention relates to an extendable/contractible strap and a bag provided with the same.
2. Description of Related Art
A bag, to which a shoulder strap (shoulder belt) is attached, is convenient, for example, when the load of the bag is heavy or when hands of a user are intended to be made free, because the bag can be retained by hanging the shoulder strap on the shoulder. Usually, the shoulder strap is detachably attached to hooks installed at right and left upper end portions of a main bag body. However, when the shoulder strap is not used, the shoulder strap hangs down from the main bag body, which gives an unseemly appearance. Further, the shoulder strap, which hangs down from the main bag body, may be caught by any object or obstacle, possibly resulting in any accident in some cases. Furthermore, when the bag is temporarily placed on the floor in the airport or on the platform of train, the shoulder strap contacts with the floor, which is unfavorable in view of hygiene.
Japanese Patent Application Laid-Open No. 10-117827 discloses a shoulder belt-equipped bag comprising a belt holder provided at a gusset portion of the bag with a belt end which is stickable to the bag by the aid of a Velcro tape. The bag has its shoulder belt which is wound around the outer circumference of the bag. When it is intended to use the shoulder belt, the following operation is performed. That is, the belt end is detached from the bag, and the belt is adjusted to have a desired length. Subsequently, the belt is fixed with the holder. Finally, the belt end is stuck to the bag with the Velcro tape or the like. However, in the case of this bag, it is necessary to attach, to the bag, unique parts such as the belt holder and the Velcro tape. Further, the bag involves the following inconveniences. That is, the bag requires the complicated operation to use the shoulder belt as well as the complicated operation to accommodate the shoulder belt. It is impossible to quickly perform such operations.
A first object of the present invention is to provide a strap and a bag provided with the same wherein the strap is shortened to have a length with which the strap does not hang down from a main bag body when the strap is not used, while the strap can be instantaneously stretched to have a sufficient length when the strap is required.
A second object of the present invention is to provide an extendable strap which is applicable to a variety of ways of use, including, for example, a strap for a portable telephone.
According to a first aspect of the present invention, there is provided an extendable/contractible strap device (15) comprising a first guide (3) which is formed with a first slit (7b) and a third slit (7a); a first strap (11) which has a first end (11a) connected to the first guide; a second guide (5) which is arranged opposingly to the first guide (3) and which is formed with a second slit (9a) and a fourth slit (9b); and a second strap (13) which has a first end (13a) connected to the second guide; wherein the first strap has a second end (11b) which passes through at least one of the second slit and the fourth slit, which returns to the first guide, and which subsequently passes through one of the first slit and the third slit of the first guide, and the second strap has a second end (13b) which passes through at least one of the first slit and the third slit, which returns to the second guide, and which subsequently passes through one of the second slit and the fourth slit of the second guide. The first end (11a) of the first strap may be connected to an intermediate or central member (3b) which is defined between the first slit and the third slit, and the first end (13a) of the second strap may be connected to an intermediate or central member (5b) which is defined between the second slit and the fourth slit.
According to a second aspect of the present invention, there is provided an extendable/contractible strap (35) comprising a first guide (23) which is defined with a first slit (27a); a first strap (31) and a second strap (33) which have first ends (31a, 33a) connected to the first guide (23) respectively; and a second guide (25) which is arranged opposingly to the first guide and which is defined with a second slit (29a); wherein the first strap has a second end (31b) which passes through the second slit (29a), which returns to the first guide, and which subsequently passes through the first slit (27a), and the second strap has a second end (33b) which passes through the second slit (29a).
According to a third aspect of the present invention, there is provided a bag (150, 180) which is provided with the strap device according to the first or second aspect of the present invention. In this specification, the term xe2x80x9cslitxe2x80x9d means an opening having a slender and rectangular configuration as well as openings having arbitrary cross-sectional configurations including, for example, circular, elliptic, and square configurations. The term xe2x80x9cstrapxe2x80x9d means a string, a cord, a band or the like having a slender and rectangular cross-sectional configuration as well as strings, cords, bands or the like having arbitrary configurations including, for example, elliptic and circular configurations.